Protocol Standards Defined by IEEE Project 802 and FDDI

Summary

IEEE Standard 802 for Local Area Networks

Recognizing a need for standards in the LAN market, the Institute of Electrical and Electronics Engineering (IEEE) undertook Project 802. Named for the year and month ('80 Feb) of its inception, Project 802 defined a family of low-level protocol standards at physical and data link layers of the OSI model.

In IEEE 802 terms, the OSI data link layer is divided into two sublayers: logical link control (LLC) and media access control (MAC).

The data link layer functions allocated to the LLC sublayer are:

Link establishment and termination

Frame traffic control

Frame sequencing

Frame acknowledgment

The data link layer functions allocated to the MAC sublayer are:

Frame delimiting

Frame error checking

Media access management

The low-level protocol standards defined by IEEE project 802 include 802.3 CSMA/CD, 802.4 token bus, and 802.5 token ring. These standards differ at the physical layer and media access control sublayer, but are compatible at the logical link control sublayer.

The 802 standards have been adopted by:

ANSI as American national standards

NBS as government standards

ISO as international standards (known as ISO 8802)

PROJECT 802 OVERVIEW

802.1--overview of project 802, including higher layers and internetworking

802.2-logical link control (LLC)

802.3-carrier sense multiple access with collision detect (CSMA/CD), very similar to Ethernet

802.4-token bus

802.5-token Ring

802.6-metropolitan area network

802.7-broadband technology advisory group

802.8-optical fiber technology advisory group

802.9-voice/data integration on LANs

802.10-standard for interoperable LAN security

ANSI FDDI STANDARD

Closely related to the IEEE 802 standards is a more recently developed low-level protocol standard known as fiber distributed data interface(FDDI) developed by the American National Standards Institute (ANSI) and based on the use of fiber optic cable.

FDDI differs from the IEEE 802 standards at the physical layer and MAC sublayer, but is compatible with the IEEE standards at the LLC sublayer.